Heretofore, lubricants for use in lubricating traction motor gears of the type employed in Diesel locomotives have comprised asphalt-oil blends, or petroleum resin-oil blends, which have been thickened with a metallic soap such as a sodium or lithium soap. These lubricants often contain extreme pressure additives, as well as corrosion and oxidation inhibitors, and antifoaming agents. An important disadvantage of soap thickened asphalt-oil, and petroleum resin-oil, based traction motor gear lubricants centers on their incompatibility with the oils used to lubricate the bearings of the traction motor. More specifically in this connection, if, due to poor gear box intergrity resulting from a defective or worn seal, leakage of the thickened lubricant occurs, and, as a result, the lubricant migrates along the traction motor armature and into contact with the motor bearing, failure of the bearing is inevitable. Replacement of the bearing is a time consuming and costly operation. A further noteworthy disadvantage of such soap thickened traction motor gear lubricants is their inability to provide proper lubrication at low temperatures. Thus, at freezing, or below freezing, temperatures the soap thickened lubricants have a gelled, or solid, consistency. In this state, they are ineffective as a gear lubricant. It is only after the gear box has heated up that the lubricants begin to perform their intended function. Yet another disadvantage encountered in the use of soap thickened traction motor gear lubricants, especially the asphalt-oil based types, is their tendency to oxidize. Oxidation acts to solidify the lubricant, rendering it useless as a lubricant, and requiring its immediate replacement. A still further disadvantage of soap thickened traction motor gear lubricants is the need for packaging them in containers, usually plastic bags, which are placed into the gear box. The action of the gears, coupled with the heat generated in the gear box, causes the bags to disintegrate thereby releasing the lubricant. The need for bags adds significantly to the manufacturing costs of the lubricants.